Most camera modules have a lens, an image-focus motor, a filter, a sensor chip, a plastic holder, and a circuit board. Currently, the plastic holder is mounted to the circuit board by optical adhesives. The plastic holder is heated, at least one escape hole or escape groove is necessary for dissipating gases and heat.
The plastic holder and optical adhesives have hygroscopicity, so the plastic holder and the optical adhesives absorb moisture in a high temperature and high humidity environment. The heat generated by the camera separates the moisture from the plastic holder and the optical adhesives. But if the separated moisture cannot escape from an outlet into the external environment it will condense on the surface of the filter to form small droplets, the small droplets will affect the image quality of the camera module. Thus, moisture needs to be expelled through the escape groove. Conventional escape groove reduces adhesive area of the adhesive between the filter and the plastic holder, which may affect the reliability of the camera module and increases risk of rupture of the filter if the camera module is impacted.
Therefore, there is room for improvement in the art.